The theme of the Pacific Northwest Center for Human Health and Ocean Sciences is elucidation of the mechanisms that govern relationships between marine processes and public health consequences of harmful algal blooms. Consistent with RFA ES-03-003, the investigators have designed a multidisciplinary research team including faculty from several academic institutions and departments in partnership with state and federal governmental organizations to facilitate both mechanistic and applied research on production and adverse affects of harmful algal blooms. The proposed Center will be a joint collaboration effort between two top-rated academic programs, the University of Washington Schools of Oceanography, Marine Affairs, and Aquatic and Fishery Science within the College of Ocean and Fishery Science and the Department of Environmental and Occupational Health Sciences (DEOHS) in the School of Public Health and Community Medicine. Also participating, both financially and with shared expertise, are investigators from the National Atmospheric Administration (NOAA), Washington State Department of Health, Washington State Department of Ecology, the Institute for Systems Biology, and the University of Maryland. The premise underlying this research is that genetic and environmental variability defines the toxicity and dynamics of harmful algal blooms (HABs), the retention of the toxin by shellfish and the human populations that are susceptible to toxicological impacts. The theme of this Center emphasizes the importance of understanding and characterizing environmental conditions and forces that determine the development of HABs and the factors that determine human susceptibility to risk associated with exposure to these. This is responsive to the directives in the NSF and NIEHS sponsored roundtable on Oceans and Human Health.